The Swiss Travel Pass covers essentially all routes in Switzerland- at least partially (discounts vary) There are regional passes like the Jungfrau Travel Pass that offers better coverage around Wengen though.

To know which pass is the best for your specific itinerary you need to plan out all trips you will make (train, bus, boat, cable car) and compare the prices for regular tickets to the rail pass price (and which routes/mountains are free or discounted). Once you have that information you can read our page here on how to choose the best rail pass. There is a spreadsheet there to help with the math. :)

Although you might want to go from Geneva to Wengen using the Golden Pass Line (www.myswissalps.com/go ldenpass) which is not possible with the Swiss Transfer Ticket which requires you to follow the most direct route offered by the SBB Timetable.